1. Field of Invention
Various exemplary embodiments of the present invention relate to a semiconductor device and a method of fabricating the same, and more particularly, to a semiconductor device having a 3-dimensional structure and a method of fabricating the same.
2. Description of Related Art
Nonvolatile memory devices are memory devices that retain stored data even when their power supplies are interrupted. Since a 2-dimensional nonvolatile memory device configured to form a memory cell in a single-layer on a silicon substrate has reached a limit in enhancing its degree of integration, a 3-dimensional nonvolatile memory device configured to vertically stack memory cells on the silicon substrate has been proposed.
The 3-dimensional nonvolatile memory device includes interlayer insulating layers and word lines, which are alternately stacked, and channel layers passing therethrough, and memory cells that are stacked along the channel layers. Further, contact plugs are formed in contact with the stacked word lines, respectively, to selectively drive the memory cells.
However, because contact plugs having various depths have to be formed in order to implement this structure, there is a high degree of difficulty in manufacturing such semiconductor devices. Further, it is likely to cause a bridge where the contact plugs pass through the word lines.